This invention relates to a device for punching out prescored portions of a sheet material so as to completely sever and remove said punched-out portions from the sheet material.
Devices for facilitating the recording of information on a record card by punching out previously scored portions of the card typically include a backing plate containing a plurality of holes corresponding to the index positions in the record card. The backing plate may also be provided with means to receive and position a record card above the plate with its index positions aligned with the holes in the backing plate. The index positions of the record cards are defined by scorings which enclose substantially but not completely the individual index positions thus weakening the bond between these areas and the surrounding portions of the record card. The prescored record card is inserted in the perforating device above the perforated backing plate and held in position by guides or other means with its index positions aligned with the holes in the base plate. The user then presses a hand-held stylus against any desired index position in the record card. The pressure thus applied on the stylus breaks the weakened index area away from the surrounding record card and forces the punched-out chip through the corresponding hole in the backing plate. In this manner, data is recorded on the card for subsequent use.
The use of perforated data cards for recording information is widespread ranging from voting ballots to payroll checks to numerically controlled machine operation. The perforations made in the data card must be of precisely defined dimensions and made in a sharp manner so as to leave the apertures thus formed free from ragged edges. The apertures thus formed in this punching process must be well defined so as to minimize the possibility of erroneous readings by the processing machine which senses the data entries. Moreover, after the stylus is inserted through a selected prescored area on the data card and is then withdrawn, the chip or card portion within the selected prescored area is frequently merely folded downwardly on the card along an edge of the aperture thus formed and remains attached to the data card. This frequently results in the reading of erroneous data from the card which is, particularly in the case of vote counting, highly undesirable.
The prior art discloses various record card processing systems and improvements in such systems. U.S. Pat. No. 2,923,452 to Holovka discloses a perforating mechanism for record cards having index positions defined by interrupted slits wherein the perforations are made by exerting force upon the area within the interrupted slits so as to rupture the connecting ties holding the bounded area integral with the record card. U.S. Pat. No. 3,240,409 to Harris similarly discloses a data registering device including a card supporting structure having a plurality of apertures upon which the data card is positioned. Also included is a frame upon which are mounted a plurality of leaf members into which a data card may be inserted. The leaf sections may then be turned in a book-like manner to expose an adjacent data card upon which data may be entered.
U.S. Pat. No. 2,949,292 to Abissi and U.S. Pat. No. 3,536,257 to Laws disclose perforating apparatus intended to insure the complete separation of a chip or card portion within a selected prescored area. The former patent includes flexed portions of a resilient backing means which close and grip the punch-out as the pressure from the punching means is removed therefrom, thus gripping the punch-out sufficiently firmly to remove it from the sheet when the work piece is removed from the apparatus. The latter patent allegedly accomplishes this end by means of a plurality of elongated slotted openings arranged in rows to match in underlying, confronting relation, prescored areas on a machine processable ballot. Each slot or opening is defined by a pair of elongated sides which are closely spaced apart and deflected downwardly and outwardly in opposite directions upon downward movement of the stylus through the slots. On upward withdrawal of the stylus after the punching operation has been completed, the edges of the slot are drawn inwardly and tightly against the stylus, and remove the punched-out chip or ballot portion from the stylus and ballot and retain the chip below the mat. While allegedly accomplishing the desired end of insuring the separation of the punched-out portion from the data card, both of the aforementioned approaches require a somewhat complex, multi-layered structure positioned beneath the data card supporting structure and increase the complexity and cost of the perforating apparatus. Also it is to be noted that all of the aforementioned approaches envision the use of a blunt-ended stylus for displacing the prescored portion of the data card. U.S. Pat. No. Des. 222,399 to Laws et al discloses a card punching stylus having a blunt engaging end which is representative of the general configuration of such devices in the prior art.
The present invention is intended to overcome the aforementioned limitations of the prior art by providing an improved and inexpensive means for perforating a prescored data card which insures the complete and well defined separation of the engaged, prescored portion of the data card without requiring additional card supporting structure to accomplish this end.